Target-date funds were invented in the early 1990s — the first “LifePath” funds launched in 1994 — as a sensible answer to a real problem: most 401(k) participants never rebalance anything. Pick the fund with your retirement year on it, and a glide path slowly shifts you from stocks to bonds as the date approaches. One decision, forty years of autopilot.
The growth, though, didn’t come from investors choosing them. It came from Washington. The Pension Protection Act of 2006 created the Qualified Default Investment Alternative — legal safe harbor for employers who auto-enroll workers into a default fund — and the Department of Labor’s implementing rule made target-date funds the default of choice for nearly every plan in America. Assets went from roughly $100 billion when the rule landed to trillions today. Most participants never picked these funds. They were placed in them. We tell that full story — QDIA, the 2006 Act, and the fee stack inside the wrapper — in our 401(k) fee audit briefing.
Then came the crisis years. In 2020 the Federal Reserve cut rates to zero and the 10-year Treasury yield bottomed near half of one percent — the lowest in the history of the republic. When yields are that low, bond prices are at record highs: you are paying the most ever for the least income ever.
A human advisor looks at that and asks whether locking in half a percent for a decade is “safe.” A glide path doesn’t ask anything. Every paycheck, every quarter, every birthday, the autopilot bought more bonds — because the calendar said so, not because the price made sense. Millions of near-retirees were mechanically loaded into the most expensive bonds ever sold.
In 2022 the Fed delivered the fastest hiking cycle in four decades, and the arithmetic of bond math took over. When rates rise, existing bond prices fall — roughly the bond’s duration multiplied by the rate move. The U.S. investment-grade bond index posted about −13%, its worst year on record; long-dated Treasuries lost roughly a third of their value — a stock-market-sized crash in the asset that was supposed to be the seatbelt.
Look at that last number. A fund built for someone three years from retirement lost nearly as much as the S&P 500’s −18% that year — because both halves of the fund fell together. The diversification that justified the bond sleeve failed at the exact moment it was being counted on.
Price change ≈ −duration × rate change. A bond portfolio with a duration of ~6.5 years, hit with a ~3-point rate rise, prices in a loss of roughly 20% — regardless of what the label on the fund says. That is not a prediction; it is how bonds are priced (see the SEC’s investor bulletin on interest-rate risk).
To be fair to the product: a target-date fund is not trying to beat the stock market. It deliberately trades upside for smoothness. But the last decade exposed three structural reasons the gap got wider than the brochure implied:
1. The permanent bond drag. Through one of the strongest equity runs in history, the glide path held an ever-growing slice in the asset class that was priced to return almost nothing — and then delivered on that pricing.
2. Valuation blindness. The rebalancing is mechanical. It bought bonds at 0.5% yields with the same confidence it would buy them at 5%. Any process that ignores price will eventually pay the wrong one.
3. The fee stack. An active target-date series runs roughly 0.60–0.78% all-in; the same glide path built from index funds costs closer to 0.08–0.12%. Paying five-to-ten times more for the wrapper compounds into six figures over a career — the fee-drag math is here.
And for our CalSTRS and CalPERS families there is a fourth reason, and it’s the one that changes decisions: your pension already is the bond sleeve. A teacher with a formula-guaranteed lifetime benefit holding a 2030 fund is paying fees to duplicate, in the riskiest bond market in decades, the safety the state already guarantees. Risk capacity — not birth year — should set the allocation. Sequence-of-returns risk is real; the question is whether a calendar or a plan should manage it.
None of this means “sell everything and buy stocks.” It means the default deserves an audit: what share class are you in, what is the all-in fee, what does the glide path assume about you that isn’t true, and what is your actual risk capacity once the pension floor is counted. That’s a twenty-minute conversation with your statement on the table.